MKV → MP3 · Extract Audio · Free · No Upload
Convert MKV to MP3 — Extract Audio Online Free
Extract MP3 audio from MKV videos directly in your browser. Free, fast, and private: the video never leaves your device.
100% local processing: your file never leaves your device. Once the page loads, it even works offline.
Supported formats:.mkv files up to 500 MB — processed locally · Video and virtually any audio format are also accepted — we extract the audio automatically.
How it works
- 01
Upload the MKV video
Drag and drop your .mkv video (up to 500 MB). Processing is local — the video is never sent to any server.
- 02
Audio is extracted in the browser
FFmpeg in WebAssembly separates the audio track from the video without needing to install anything.
- 03
Download the MP3
The .mp3 file is ready in seconds, lightweight and compatible with any player or editor.
Frequently asked questions
Why convert MKV to MP3?
OBS recordings come out in MKV — extract just the audio in MP3 to listen, edit, or transcribe the class/livestream.
What if I need the text of this audio?
After converting, you can transcribe the file with AI on VoxScriber: 30 free minutes per month, with automatic punctuation and speaker identification. Ideal for WhatsApp audios, meetings, and interviews.
Is the MKV to MP3 converter really free?
Yes, free and unlimited. Processing happens in YOUR browser (WebAssembly), so we have no server costs — and you don't need to create an account.
Is my file sent to any server?
No. All processing is local (FFmpeg compiled to WebAssembly running on the page). The file never leaves your device — it even works offline after the page loads.
Is there a size or quantity limit?
The limit is 500 MB per file (browser memory). There is no limit on number of uses. For larger files, VoxScriber processes on the server with upload up to 5 GB.
Does it work on mobile?
Yes — any modern browser (Chrome, Safari, Firefox, Edge) on desktop or mobile. On older phones, large files may take longer.
Need the text from this audio? Transcribe with AI — 30 min free
Create free account →30 minutes/month free. No credit card required.